The invention relates to a method for producing an adhesive-bound printed item composed of several printed products, for which the printed products are gathered along a first conveying section of a conveying track for a circulating conveyor and gathered into loose book blocks, and are then supplied with a following conveying section to an adhesive binder. The invention furthermore relates to an arrangement for realizing the method.
With the methods used in the print processing industry for the adhesive binding of printed products to form printed items, the individual printed products are first gathered in a gathering machine into loose book blocks, and are subsequently transferred to the conveying clamps of an adhesive binder. The transfer from the gathering machine to the adhesive binder among other things involves the function of taking over the gathered loose book blocks, which move at the speed and with the orientation of the gathering machine, and to transfer these book blocks to the adhesive binder at the speed of the adhesive binder.
According to a one known system, the book blocks can be conveyed in the gathering machine while positioned upright and in the direction of the book block spine, inside a conveying channel with a V-shaped cross section that is inclined slightly counter to the back fold. The book blocks are transferred in a vertical plane to the adhesive binder, which also moves in a longitudinal direction of the spine, wherein the back folds of the book blocks are oriented in a downward direction. Inside the gathering machine, the book blocks are normally conveyed form-fittingly with the aid of pushers attached to chains, which push along the book blocks. If no optional processing of the book blocks is required inside the transfer region, such as vibrating, adding sections, gluing on of end sheets, wire-stitching, printing, and the like, then the book blocks need only to be moved from a slightly inclined position to an upright position during the conveying in the longitudinal direction of the spine. If the gathering machine stops, the adhesive binder can continue to operate and finish the processing of the remaining book blocks. As a result, the divisional spacing between successively following book blocks of necessity increases while the conveying speed becomes relatively high. The conveying speed thus can be the limit speed for a maximum production speed. Above all, this applies to the channel region of the gathering machine where the conveying operation generates turbulence in the air, which in turn causes buoyancy forces for the top printed products of the loose book blocks that can lift up these sheets from the book blocks. An additional disadvantage of this solution manifests itself when the gathering machine is stopped because the loose book blocks shoot forward as a result of their kinetic energy, which may cause a loss of orientation.
A different solution according to another known system is disclosed in European Patent Application 0 675 005 B1, which calls for the loose book blocks to be conveyed inside the adhesive binder while positioned transverse to the longitudinal direction of the spine. The conveying speed can thus be reduced while the production speed remains the same, as compared to a conveying in the longitudinal direction of the spine. The disadvantage of this principle is that the adhesive binder requires a complicated configuration.
According to published European Patent Application 1 528 023 A1, the printed sheets, which are positioned transverse to the longitudinal direction of the spine on a conveying belt, are gathered to form overlapping flows and are then separated into individual book blocks just prior to the transfer to an adhesive binder which moves in longitudinal direction. Following the separation, the individual book blocks are transferred to laterally moving compartments and placed in the upright position, so that the book block spines point downward. They are subsequently deflected by an angle of 90° and moved to a conveyed flow in which they are conveyed with the spine aligned in conveying direction. The disadvantage of this method is that book blocks having thicker or smaller formats, as well as book blocks with a rigid content such as CD's, cannot be processed.